<!DOCTYPE HTML>
<html>
<body>
    <div style="text-align: center;">
        <button onclick="playPause()">播放/暂停</button>
        <button onclick="makeBig()">大</button>
        <button onclick="makeNormal()">正常</button>
        <button onclick="makeSmall()">小</button>
        <br>
        <video id="v1" width="1080" height="720" controls="controls"    >
            <source src="http://vfx.mtime.cn/Video/2019/03/19/mp4/190319212559089721.mp4" type="video/mp4">
            <!--contorlscontrols 属性规定浏览器应该为视频提供播放控件。
            autoplay="autoplay"   属性为自动播放 -->
            </video>
            <script type="text/javascript">
            var myVideo=document.getElementById("v1");
            function playPause()
            { 
                if (myVideo.paused) 
                myVideo.play(); 
                else 
                myVideo.pause(); 
                } 
                function makeBig()
                { 
                    myVideo.width=560; 
                } 
                function makeSmall()
                { 
                    myVideo.width=320; 
                } 
                function makeNormal()
                { 
                    myVideo.width=420; 
                } 
            </script>
            <!--一个js功能-->

            <br>
            <br>
        <audio src="http://music.163.com/song/media/outer/url?id=418708385.mp3" autoplay="autoplay"><!--加 controls="controls"添加控制条-->
        </audio>
        <!--分别插入视频和音频文件-->
        </div>
</body>
</html>